Unique identity? Super strats are far from unique. The formula has been on the scene well over 3 decades. No less a guitar... but not unique. Ronin, Koll, Forsage, and Teuffel are some examples of unique identities.Suhrs, Andersons and other "super strats" I think have established a unique identity.
Regarding any guitars appreciating in value? I'm not confident in any major trends in appreciation. Maintaining value? Sure some will. But I don't believe there will ever be any sort 1950/60's vintage value treatment of any contemporary guitars.